Acne disorders are often classified as noninflammatory or inflammatory types. Noninflammatory acne is characterized by closed comedones (whiteheads) and open comedones (blackheads), consisting of compact masses of keratin, sebum, and bacteria, which dilate the follicular duct. A comedone forms when a pilo-sebaceous duct is obstructed and/or when there is increased production of sebum by a sebaceous gland. Formation of the comedone can be followed by inflammation, resulting from bacterial proliferation and/or overproduction of sebum. Typically, the bacteria are anaerobic bacteria such as Propionibacteria (P. acnes). Inflammatory acne is characterized by papules (pimples), pustules, and nodulocystic lesions which may lead to scarring. Several factors are believed to play important roles in the pathogenesis of acne including: sebum production, hormonal stimulation, plugged pores, and skin pathogens. Sebum levels are increased in subjects with acne by approximately 70% compared to sebum levels of control subjects.
The present invention relates to the unexpected discovery that extracts of primula denticulata are topically effective for treating acne and reducing the appearance of oil or pores on the skin.